I compiled a minimal boot image, maybe some of you want to give it a try. Just extract the files on a SD and do the usual flashing. The updater.sh is from my Debian-experiment, but it works nicely. It boots on my C3100, that's all it does so far. What has to be done next is described in the instructions here (copy ramdisk.img.gz, system.tar.gz and data.tar.gz, extract it, etc). I'll try tomorrow, but now it's time to get some sleep